{"api_version":"1","generated_at":"2026-10-21T17:18:06+00:00","cve":"CVE-2026-98794","urls":{"html":"https://cve.report/CVE-2026-98794","api":"https://cve.report/api/cve/CVE-2026-98794.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98794","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98794"},"summary":{"title":"ipvs: filter some flags received in the backup server","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nipvs: filter some flags received in the backup server\n\nWhile the IPVS SYNC protocol is not secure by design\nwe can still protect the backup server from messages that\ncan wreak havoc.\n\nThis commit addresses problems from received connection flags\nor their combinations. We now drop messages as follows:\n\n1. the NO_CPORT+TEMPLATE combination allows lookups for normal\nconnections to hit template which can break in many ways.\nWhile the master does not sync connections with NO_CPORT flag,\ni.e. before they are established, we still accept NO_CPORT\nwithout TEMPLATE.\n\n2. ONE_PACKET: it is not sent by master, so we do not\nexpect it in backup. Before now it was ignored by\nIP_VS_CONN_F_BACKUP_MASK for protocol v1 while protocol\nv0 created connections that are not hashed and dropped\nimmediately. Better to apply the IP_VS_CONN_F_BACKUP_MASK\nalso to the flags from v0 messages for consistency with v1.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-10-18 16:17:33","updated_at":"2026-10-21 13:21:47"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/55d033324f67a15ff56be6d38d6e87f644e0ed62","name":"https://git.kernel.org/stable/c/55d033324f67a15ff56be6d38d6e87f644e0ed62","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/45a93111835ccfea7d969ec73588e33745fd9834","name":"https://git.kernel.org/stable/c/45a93111835ccfea7d969ec73588e33745fd9834","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f4cd1db7d421e82945713a36084bb0c35b75b27e","name":"https://git.kernel.org/stable/c/f4cd1db7d421e82945713a36084bb0c35b75b27e","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f96e91748f6304668fe647e686d199d7207d36f1","name":"https://git.kernel.org/stable/c/f96e91748f6304668fe647e686d199d7207d36f1","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d7d33c9efa9d1a2f244a1a64ec9b540b0f8975a0","name":"https://git.kernel.org/stable/c/d7d33c9efa9d1a2f244a1a64ec9b540b0f8975a0","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98794","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98794","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 87375ab47cd0ba04124c6d3fd80db5c368f5dcb6 d7d33c9efa9d1a2f244a1a64ec9b540b0f8975a0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 87375ab47cd0ba04124c6d3fd80db5c368f5dcb6 f4cd1db7d421e82945713a36084bb0c35b75b27e git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 87375ab47cd0ba04124c6d3fd80db5c368f5dcb6 55d033324f67a15ff56be6d38d6e87f644e0ed62 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 87375ab47cd0ba04124c6d3fd80db5c368f5dcb6 45a93111835ccfea7d969ec73588e33745fd9834 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 87375ab47cd0ba04124c6d3fd80db5c368f5dcb6 f96e91748f6304668fe647e686d199d7207d36f1 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2.6.14","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 2.6.14 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.160 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.113 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.56 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.10 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/netfilter/ipvs/ip_vs_sync.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"d7d33c9efa9d1a2f244a1a64ec9b540b0f8975a0","status":"affected","version":"87375ab47cd0ba04124c6d3fd80db5c368f5dcb6","versionType":"git"},{"lessThan":"f4cd1db7d421e82945713a36084bb0c35b75b27e","status":"affected","version":"87375ab47cd0ba04124c6d3fd80db5c368f5dcb6","versionType":"git"},{"lessThan":"55d033324f67a15ff56be6d38d6e87f644e0ed62","status":"affected","version":"87375ab47cd0ba04124c6d3fd80db5c368f5dcb6","versionType":"git"},{"lessThan":"45a93111835ccfea7d969ec73588e33745fd9834","status":"affected","version":"87375ab47cd0ba04124c6d3fd80db5c368f5dcb6","versionType":"git"},{"lessThan":"f96e91748f6304668fe647e686d199d7207d36f1","status":"affected","version":"87375ab47cd0ba04124c6d3fd80db5c368f5dcb6","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/netfilter/ipvs/ip_vs_sync.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"2.6.14"},{"lessThan":"2.6.14","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.160","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.113","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.56","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.10","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.160","versionStartIncluding":"2.6.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.113","versionStartIncluding":"2.6.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.56","versionStartIncluding":"2.6.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.10","versionStartIncluding":"2.6.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3","versionStartIncluding":"2.6.14","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nipvs: filter some flags received in the backup server\n\nWhile the IPVS SYNC protocol is not secure by design\nwe can still protect the backup server from messages that\ncan wreak havoc.\n\nThis commit addresses problems from received connection flags\nor their combinations. We now drop messages as follows:\n\n1. the NO_CPORT+TEMPLATE combination allows lookups for normal\nconnections to hit template which can break in many ways.\nWhile the master does not sync connections with NO_CPORT flag,\ni.e. before they are established, we still accept NO_CPORT\nwithout TEMPLATE.\n\n2. ONE_PACKET: it is not sent by master, so we do not\nexpect it in backup. Before now it was ignored by\nIP_VS_CONN_F_BACKUP_MASK for protocol v1 while protocol\nv0 created connections that are not hashed and dropped\nimmediately. Better to apply the IP_VS_CONN_F_BACKUP_MASK\nalso to the flags from v0 messages for consistency with v1."}],"providerMetadata":{"dateUpdated":"2026-10-21T12:57:03.851Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/d7d33c9efa9d1a2f244a1a64ec9b540b0f8975a0"},{"url":"https://git.kernel.org/stable/c/f4cd1db7d421e82945713a36084bb0c35b75b27e"},{"url":"https://git.kernel.org/stable/c/55d033324f67a15ff56be6d38d6e87f644e0ed62"},{"url":"https://git.kernel.org/stable/c/45a93111835ccfea7d969ec73588e33745fd9834"},{"url":"https://git.kernel.org/stable/c/f96e91748f6304668fe647e686d199d7207d36f1"}],"title":"ipvs: filter some flags received in the backup server","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98794","datePublished":"2026-10-18T15:48:37.924Z","dateReserved":"2026-09-25T10:25:14.370Z","dateUpdated":"2026-10-21T12:57:03.851Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-10-18 16:17:33","lastModifiedDate":"2026-10-21 13:21:47","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98794","Ordinal":"1","Title":"ipvs: filter some flags received in the backup server","CVE":"CVE-2026-98794","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98794","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nipvs: filter some flags received in the backup server\n\nWhile the IPVS SYNC protocol is not secure by design\nwe can still protect the backup server from messages that\ncan wreak havoc.\n\nThis commit addresses problems from received connection flags\nor their combinations. We now drop messages as follows:\n\n1. the NO_CPORT+TEMPLATE combination allows lookups for normal\nconnections to hit template which can break in many ways.\nWhile the master does not sync connections with NO_CPORT flag,\ni.e. before they are established, we still accept NO_CPORT\nwithout TEMPLATE.\n\n2. ONE_PACKET: it is not sent by master, so we do not\nexpect it in backup. Before now it was ignored by\nIP_VS_CONN_F_BACKUP_MASK for protocol v1 while protocol\nv0 created connections that are not hashed and dropped\nimmediately. Better to apply the IP_VS_CONN_F_BACKUP_MASK\nalso to the flags from v0 messages for consistency with v1.","Type":"Description","Title":"ipvs: filter some flags received in the backup server"}]}}}